1. Field
The present disclosure relates generally to rocket propelled vehicles. More particularly, the present disclosure relates to a method and apparatus for a common bulkhead for composite propellant tanks.
2. Background
High altitude aircraft, missiles, launch vehicles and satellites are examples of vehicles which may be rocket propelled. These rocket propulsion systems may use liquid or gaseous propellants. Liquid propellants may include, for example, without limitation, liquid hydrogen and/or liquid oxygen. Other common combinations include kerosene with liquid oxygen or the storable hypergolic propellants mono-methyl hydrazine with nitrogen tetroxide.
Propellants are stored in tanks. When more than one tank is present, common walls may be interposed between the tanks. This common wall may also be referred to as a common bulkhead. These types of tanks are often comprised of metal. However, recently, tanks comprised of composite materials have also been used. Tanks comprised of composite materials may result in lower vehicle weights, as compared to metal tanks.
Two propellants may be stored in two tanks having a common wall. Pressure within the tanks may be different on the two sides of the common wall between the two tanks. The common wall may be designed to resist undesired structural changes resulting from this differential pressure and/or other vehicle loads. For many common bulkhead applications, it is desirable that undesired structural changes be reduced and/or prevented with as little weight as possible. For example, sandwich construction bulkheads may be comprised of facesheets on either side of a connecting lightweight core. These types of bulkheads are lighter for a given load resistance or more structurally efficient, as compared to a simple monocoque membrane or skin and stiffener construction.
The rocket propellants stored in tanks are used for their ability to react energetically. Bulkheads may be used in fuel tanks to separate propellants. Currently used bulkheads may provide an undesired transfer of heat.
Therefore, it would be advantageous to have a method and apparatus that takes into account one or more of the issues discussed above, as well as possibly other issues.